A young woman was taken to hospital after suffering head injuries when she fell 10ft (3m) on to rocks.
Emergency services were called to the Merchant Adventures Hall, by the River Fosse in York, at 2330 BST on Saturday after reports a woman had fallen.
It is thought she had gone for a swim in the river and then fallen on to the rocks as she tried to get out.
Fire crews winched the 21-year-old to safety and she was taken to York District Hospital for treatment.